Former Pakistan captain Salman Butt.

Islamabad – Salman Butt has asked Pakistan's chief justice to look into the spot-fixing scam that led to the banned former captain serving a prison term in England.

Butt returned home last Friday after being freed from Canterbury Prison in England, having completed seven months of a 2 1/2-year sentence for fixing.

Butt told private television channel Express News on Thursday that he knows nothing about the pre-determined no-balls bowled by fast bowlers Mohammad Amir and Mohammad Asif in a Test against England at Lord's in 2010 and said chief justice Iftikhar Chaudhry should reopen the case.

Butt was banned for 10 years – five of which are suspended. However, he now plans to file an appeal against the ban in the Court of Arbitration for Sport. – Sapa-AP